Q about replaceable derailleur hangers

[smontanaro]

I have nothing in my fleet with a replaceable derailleur hanger. (Everything is steel, brazed into the steel stays.) My understanding is hangers are in some sense "sacrificial." They break, not your expensive frame or derailleur. Am I more-or-less right about the rationale?

If so, I'm totally confused about an email I got from Silca touting titanium derailleur hangers. I can't get to the Silca site just now, but it's this URL:

https://silca.cc/collections/derailleur-hanger

Wouldn't replacing typical aluminum(?) derailleur hangers with titanium increase the odds that something much more precious is sacrificed in case of a crash or other unanticipated problem?

[Carbonita]

(probably should move this thread to General Forum) According to Josh Poertner, it's designed to fracture or deform before frame damage, but no test data has been provided.

[bikinchris]

Unless the titanium derailleur hanger is made to fail, it wouldn't be a good idea. The only reason for the hanger to fail is to save the frame from expensive damage.
BTW, you can bend a steel dropout and bend it back. You absolutely can NOT do that if the aluminum, carbon or even titanium frame has the same damage.

[redir]

They make sense on carbon and AL bikes where bending and fatigue are an issue. I've had a few warp in the past on steel and Ti bikes and had the bike shop simply bend them back. I find them annoying really.

[Carbonita]

UDH and T-type systems purport to improve the system. And Shimano has a competing patent, cuz, of course.

[Tandem Rider]

I've gone through a few aluminum hangers on aluminum and carbon frames, they are pretty cheap, I try to keep a spare on hand for any bike I ride very much. They are "somewhat" tuneable with a hanger tool (I've never broken one truing it up) and toast after a significant bend, cracks or sheared off. All the steel frames I've ever had have steel hangers and I just true them up after an impact or "incident", they usually don't bend very much, the derailluer takes the hit instead of the hanger.

[rice rocket]

Originally Posted by Carbonita

UDH and T-type systems purport to improve the system.

Purport to lock you into buying $600 cassettes.

It'll be interesting to see how this shakes out or if the bike industry rejects SRAM's attempt to vertically integrate into all proprietary components while doubling the price on consumables.

[slowpoke]

Originally Posted by rice rocket

It'll be interesting to see how this shakes out or if the bike industry rejects SRAM's attempt to vertically integrate into all proprietary components while doubling the price on consumables.

In the MTB world, I feel like the UDH is becoming the standard on for better or worse. One of the Neuhaus folks has proposed an open source standard that I'd love to see catch on.

Originally Posted by smontanaro

Wouldn't replacing typical aluminum(?) derailleur hangers with titanium increase the odds that something much more precious is sacrificed in case of a crash or other unanticipated problem?

Buried in the product descriptions is this:

SILCA 3DP Hangers are able to be aligned by hand, and are designed with an internal fracture notch which allows the hanger to fracture and bend below the point of damage for the carbon frame to eliminate the risk of frame damage under the hardest of impacts.